1. Technical Field
The present invention relates to a technology that applies tension to a sheet being transferred.
2. Related Art
The printer in Japanese Laid-Open Patent Publication No. 2013-111780 is provided with a feeding shaft and a take-up shaft that support the respective end of a sheet, and transfers the sheet from the feeding shaft to the take-up shaft by rotating the feeding shaft and the take-up shaft. In addition, this printer ejects light-curable inks onto the sheet during the transfer from the feeding shaft to the take-up shaft, and irradiates light onto the inks. Thus, a sheet having an image formed from cured light-curable inks is wound onto the take-up shaft.
In addition to the forward transfer that transfers the sheet from the feeding shaft to the take-up shaft as described above, the printer is sometimes configured to conduct a backward transfer that transfers the sheet from the take-up shaft to the feeding shaft. In a printer capable of performing this type of backward transfer, the rotation shafts of the take-up shaft and the feeding shaft are required to have the function of feeding the sheet, and not only the function of winding the sheet. In this case, from the perspective of stable feeding of the sheet, adequate tension is appropriately applied to the sheet. Therefore, a configuration is considered in which a high tension is applied to the sheet from the rotation shafts.
However, this configuration is advantageous for feeding the sheet from a rotation shaft, but cannot be said to be advantageous for winding the sheet onto a rotation shaft. That is, an image formed by curing light-curable inks is thicker compared to, for example, an image formed from water-based inks. Therefore, because a high tension was applied to the sheet by the rotation shaft, the problem was that when the image formed on the sheet was wound at a high tension to the rotation shaft, unevenness caused by the thickness of the image developed in the wound sheet.